The invention relates to a method for readily assembling a packaged microcircuit with face-mounted leads.
In a common type of unpackaged microcircuit, circuit paths are formed on a face of a substrate and terminals are disposed along the edges of the substrate. A microcircuit of this type can be packaged in a housing and connected to leads that extend through the sides of the housing to contact its terminals. A microcircuit of this type can also be packaged without a housing, and with leads that are terminated in lead-receiving recesses along an edge of the substrate. In both styles of packaged microcircuits, the leads are inserted and seated in lead-receiving recesses before the conventional solder connections are made.
In the mass production of packaged microcircuits it has been found advantageous and economical to use lead frames. These frames carry a plurality of leads that can be inserted in sets into lead-receiving recesses in a plurality of microcircuits, simultaneously, as shown in Wallick, U.S. Pat. No. 4,012,835.
In certain types of microcircuits, circuit design has been improved by locating terminals on the face of the substrate and away from its edges. This type of microcircuit, however, is not easily packaged with existing lead frame methods. This is because the leads cannot be held down on these face terminals with the force required to insure adequate solder connections using conventional mass soldering techniques.